Outline

Objective: Endovascular occlusion is currently regarded as first choice treatment option for most intracranial aneurysms. However, middle cerebral artery (MCA) aneurysms are usually treated by microsurgical clipping due to their unique anatomical features. In this study, indications for surgery and outcome of patients with ruptured MCA aneurysms, who underwent microsurgical clipping, were evaluated.

Methods: Between 2004 and 2010 a series of 70 patients with ruptured MCA aneurysms, which were admitted to our institution were evaluated retrospectively. Initial clinical grade was classified according to the Glasgow Coma Scale (GCS), Hunt & Hess grade (HH) and the appearance of subarachnoid hemorrhage on baseline CT-scan (Fisher grade). Indication for surgery was assessed retrospectively from the patients’ records. The Glasgow Outcome Scale (GOS) was used to assess the clinical outcome. It was classified as favorable (GOS 4–5) or unfavorable (GOS 1–3). Radiological findings in postoperative CT scan and digital subtraction angiography (DSA) were assessed.

Results: Average age was 53.8 years (range 25–84 years). HH grade was 1–3 in 50% (n=35) and grade 4–5 in 50% (n=35). In 51 cases (72.9%) space-occupying intracerebral hemorrhages (ICHs) were observed (Fisher grade 4). During the 70 surgical procedures 76 aneurysms were clipped. 32 of the 76 aneurysms were small-sized (1–5 mm), 29 aneurysms were of medium size (6–10 mm) and only 15 aneurysms were large-sized (>11 mm). The presence of space-occupying ICHs was the most frequent indication for surgical treatment of the aneurysms followed by wide neck complex aneurysms and arterial branches arising from the neck and/or dome. Postoperative DSA showed an incomplete aneurysm clipping in 9 cases (12.9%). In six of these incomplete clipping was performed deliberately in order to preserve arterial branches arising from the parent vessels. In cases of a good initial clinical grade (HH 1–3) 25 patients (71.4%) showed a favorable outcome and no patient died in this group. Among the patients with poor initial clinical grade (HH 4–5) a favorable outcome was achieved in only 8 cases, whereas 9 patients died in this group.

Conclusions: The initial clinical grade was the most important predicting factor for the patients’ outcome. Indications for surgery were (1) the presence of ICH and (2) a complex anatomy. The latter increases the risk for incompletely occluded aneurysms. These individuals require radiological follow-up examinations to detect aneurysm re-growth.